As RTE executives unveiled their shiny new shows last week, one figure stood out because of his penchant for the abyss and giant whales, instead of studio audiences and make-up brushes.

Ken O'Sullivan is an underwater cameraman who dives into the North Atlantic, collecting footage of sea creatures big and small. He has come within inches of gigantic blue whales, octopus, rare fish and beautiful coral.

Often, he does so without the aid of an oxygen tank, relying solely on his body to survive and react as he comes within inches of endangered creatures.

"You just hold your breath," he says modestly.

"The reason we have to do that is to be able to keep up with the whales. They are always moving and never really stop, so you are trying to get into their path.It is very important not to disturb them in any way.

''You have to be able to move and scuba tanks are just too bulky. I am also holding a camera so I can't use my arms to swim, I can only kick my fins.

"You have to try and get to that whale pretty quickly, swim 40 or 50 metres and then dive down. The maximum we are diving to is 10 or 15 metres but it is pretty physical."

An experienced diver, Ken admits he has lived somewhat of a Huckleberry Finn existence. He is based in Lahinch but spent summers as a child in Fenit, Co Kerry, fishing and swimming in Tralee Bay. This has helped him cope with the demands of swimming underwater without an oxygen supply but he maintains, in GAA terms, that he is nowhere near Croke Park yet.

"One of the problems is I can hold my breath for two minutes in a swimming pool, but if you just swam 30 or 40 metres then it is a real challenge to catch your breath again.

"I did some training with a Russian woman earlier on in the year. She has dived to 94m holding her breath so I really am at Junior B level."

For the past 18 months he has been filming Ireland's Deep Atlantic, a three part-series which will offer a glimpse into the world that exists on the ocean floor off the west coast.

He hopes the filming will wrap up before Christmas and the show is pencilled in to appear in living rooms nationwide in 2018.

"We are going out to sea again this evening," he says as he gets ready for a dive. "We have probably been researching it for six or seven years. I made my first trip out in 2011 so, between researching and thinking about it and trying to film it, we have been at this a while.

"I am just trying to document it because this is very much where I come from, this is where my identity is and I just want to document what's here."

Ken has been making wildlife documentaries with Sea Fever Productions since 2006.

He aims to show viewers the importance of conserving the natural landscape 5,000m below the surface of the North Atlantic.

"Blue whales are the largest animal known to exist and they pass through those waters, all kinds of predators, sharks, and then on the seabed, a place that people thought for thousands of years was a dark, empty abyss.

''Luckily we were able to get a submarine down there with the Marine Institute and the Celtic Explorer, the Irish State Research vessel. They have a remotely operated underwater vehicle so we were able to get cameras on that and send it down."

He said this was essential to see what lurks in the depths that are too deep for divers to reach, even with the aid of an oxygen tank.

"What we found was anything but the deep dark abyss," says Ken.

"It is full of beautiful coral reefs, all kinds of elements of creatures living there, like crabs, shellfish, crustaceans, octopi.

"There are hundreds of thousands of species living in that area, all in beautiful colours. They live in complete darkness, so it is only when you put the light on in the sub that you can see them."